Compensation Methods for pH Direct Measurement in Soilless Culture Substrates Using the All-Solid-Stated pH Sensor

Rapid and High-Performance Analysis of Total Nitrogen in Coco-Peat Substrate by Coupling Laser-Induced Breakdown Spectroscopy with Multi-Chemometrics

“…Some main steps of this method include the following: (1) samples were despoiled in a despoiling furnace; (2) an automatic nitrogen determinator was used to distill the boiled sample; (3) the nitrogen in the sample was converted into NH 3 by distillation, and then the boric acid solution with acid-base indicator was used to absorb NH 3 ; and (4) an acid standard solution was applied to titrate the boric acid solution that absorbed NH 3 . TN values could be calculated by hydrochloric acid consumption, and the calculation formula is as shown in (1).…”

“…Substrate culture is a soilless culture technology that uses solid media instead of soil to fix plant roots and provide nutrients through the substrate [1]. This technology can achieve high-quality and high-yield planting through the scientific management of water and fertilizer and precise environmental regulation [2].…”

“…To solve the influence of the matrix effect and atmospheric nitrogen on the detection of TN in coco-peat substrate, argon injection, variable screening and multivariate modeling were combined to achieve rapid and high-performance detection of TN in coco-peat substrate, thus providing a basis for scientific fertilization decision-making. The specific works were as follows: (1) The optimal argon flow rate for the LIBS detection of TN content in coco-peat substrate was determined. (2) Spectral detection model of coco-peat substrate TN based on univariate calibration curve was established, and PLSR was used to construct the LIBS detection model of TN in coco-peat substrate based on full variable spectral data.…”

Statistical methods and experimental design for agreement and similarity studies between open-source software and hardware devices, and corresponding agriculture technology (agritech) market devices

“…Therefore, direct measurement appears to be suitable for frequent, rapid, and accurate pH measurement in soilless culture substrate. However, the large error of this technique still needs to be solved (Chen et al, 2021).…”